1. Field of the Invention
The present invention relates to an image forming apparatus mountable in a limited amount of space and, more particularly, to a laser beam printer mountable in a limited amount of space.
2. Description of the Related Art
Japanese Examined Patent Publications Nos. 6-97354 and 7-40168 disclose laser beam printers to which a process unit, accommodating a photosensitive drum, and a consumable article, such as toner, is detachably attached.
In a printer disclosed in the Japanese Patent Publication 6-97354, space must be provided above the printer to facilitate replacement of the process unit. Thus, the space above the printer cannot be freed for effective use.
In a printer disclosed in the Japanese Patent Publication 7-40168, an attaching/detaching direction of a paper feed cassette is perpendicular to a mounting direction of a process unit. Specifically, the paper feed cassette is pulled out to the front from the printer, while the process unit is pulled out to the right therefrom. Accordingly, space for attaching/detaching the paper feed cassette, as well as space for replacing the process unit, are required at the front and on the right side of the printer, respectively. As a result, a footprint of the printer, i.e., the required size of the surface on which the printer is disposed, is increased.
It is therefore an object of the invention to provide an image forming apparatus that has a small footprint, and thereby enables space around the printer to be freed for effective use.
To attain this object, in an image forming apparatus according to the invention, a paper feed cassette accommodating unit, an image forming unit, and a paper discharge unit are arranged vertically within a housing. Accordingly, the footprint of the image forming apparatus can be reduced.
Further, an opening for attaching/detaching a process unit and another opening for attaching/detaching a paper feed cassette are formed on the front face of the housing. Thus, it is unnecessary to open the upper surface of the housing. Since both the opening for attaching/detaching the process unit and the opening for attaching/detaching the paper feed cassette are provided on the front face of the housing, the same space that is used for attaching/detaching the paper feed cassette can be used for attaching/detaching the process unit. Accordingly, it is unnecessary to take the trouble to open the periphery of the image forming apparatus prior to attaching/detaching the process unit. As a result, the operations of attaching/detaching are facilitated, and the footprint of the image forming apparatus can be reduced.
It is preferable that the process unit is designed to be detachably attached to the housing in a direction perpendicular to an axial direction of a photosensitive drum that is accommodated in the process unit.
In this case, the attaching/detaching direction of the process unit and a paper discharge direction can be easily made to be the same. Further, the attaching/detaching direction of the paper feed cassette can be easily made to be the same (directed to the front). Accordingly, it is unnecessary to open sides of the apparatus other than the front side. As a result, the footprint can be reduced and space around the image forming apparatus can be freed for effective use.
A laser scanner may be disposed above the process unit within the housing.
In this case, the laser scanner will not interfere with the process unit when the process unit is attached/detached from the front side of the housing. Thus, it is unnecessary to move the laser scanner prior to attaching/detaching the process unit. Since the laser scanner can be moved upward without opening the upper portion of the housing, space above the housing can be freed for effective use.
Further, it is preferable that the upper surface of the housing is made to be planar. In this case, another device can be placed on the upper surface of the housing, and space for paper discharged by a paper discharge unit can be provided below the device. Thus, space above the housing can be effectively used.
The paper discharge unit may be accommodated within the housing, and an opening for removing paper discharged by the paper discharge unit may be provided in the housing. In this case, paper discharged by the paper discharge unit can be removed through the opening, while space above the housing is available for effective use.
Further, when a leading edge of paper discharged by the paper discharge unit is arranged to project outwardly from the front of the housing, discharged paper can be readily removed.
Further, the upper surface of the housing is made to be detachable. The upper portion of the paper discharge unit can then be opened when needed.
Still further, an operation panel accepting a user""s operations and an insertion slot for allowing manual paper insertion may be provided on the front face of the housing.